The present invention is directed to bicycle braking devices and, more particularly, to a ventilated brake pad for a bicycle disc brake.
Bicycling is becoming an increasingly popular form of recreation as well as a means of transportation. Moreover, bicycling has become a very popular competitive sport. Whether the bicycle is used for recreation, transportation or competition, the bicycle industry is constantly improving the bicycle components. One particular component of the bicycle, which has been extensively redesigned over the past years, is the braking system. As a result, there are several types of bicycle brake devices currently available on the market. Examples of some types of common bicycle brake devices include rim brakes, caliper brakes and disc brakes. If a rider wants a very high performance brake system, then the rider typically prefers a disc brake system wherein brake pads press against a brake disc that rotates with the bicycle wheel. Disc brake systems provide a substantial braking power in relationship to the amount of braking force applied to the brake lever. Moreover, disc brake systems typically provide a high level of consistency in all types of weather and riding conditions.
Unfortunately, one problem with disc brakes is that a tremendous amount of heat is generated by the frictional contact between the brake pads and the brake disc that is rotating very rapidly with the wheel. When the disc brake is operated by hydraulic pressure, the heat can cause the brake fluid to expand. This, in turn, causes the phenomenon known as vapor lock wherein the brake pad is pressed against the brake disc even when the brake control mechanism is released. To prevent this phenomenon, some braking systems provide an insulator between the brake pad and the piston used to press the brake pad against the brake disc. While such insulation can prevent heat transfer from the brake pad to the hydraulic components to minimize or prevent vapor lock, the inability to dissipate the heat tends to create excessive heat between the brake pad and the brake disc. This, in turn, causes the frictional contact to be less effective and risks warping the brake disc.